GGT1 and neoplasm: Moreover, the complexity of the GGT gene family has been explored at multiple levels, and the aberrant expression and prognosis of GGT1, GGT2, GGT5, GGT6, GGT7, GGTLC1, GGTLC2, and GGTLC3 in multiple tumors, as well as the mechanism of transcriptional regulation, such as tumor‐specific expression of different promoter‐driven products, have been analyzed in detail.